[Cryptography] Crypto and rustling

[Peter Gutmann]

Dave Horsfall <dave at horsfall.org> writes:

>The problem for the owner was that their brands could easily be altered into
>another brand, so what I'm asking is that using the technology of the day
>viz: branding irons, could it have been prevented?  An interesting
>intellectual exercise...

I think your options are somewhat limited when your medium is burnt animal
hair and you've only got access to 19th-century technology, thus the
suggestion to look at alternative approaches.  At best you could design your
brand to have the maximum Hamming distance between it and any other registered
brand in order to make alteration difficult, but I assume that was being done
by the different ranches anyway.  You could use a variant of the Histiaeus
trick of shaving a patch of your cow, tattooing something in there, and
waiting for it to grow over.  If you saw any shaved cows wandering around,
you'd know that cattle rustlers were looking for your stego.  Then you'd need
a trusted referee who could verify the stego without revealing its details,
which probably wouldn't have worked in any 19th-century legal jurisdiction
because it'd be indistinguishable from the rich ranch owner bribing the
referee to rule in his favour.

>> Some problems are most easily solved by moving the goalposts to where 
>> the ball is going, not the other way round.
>
>Can I quote you on a .signature?

Sure.  It's just stating common sense though...

Peter.